Rolling mill for rings and discs



March 29, 1960 E. H. KENDALL 2,930,266

ROLLING MILL FOR RINGS AND DISCS Filed July 28, 1954 4 Sheets-Sheet l q=u i E- 4 INVENTOR EDGAR HOMER KENDALL March 29, 1960 E. H. KENDALL 2,930,266

ROLLING MILL FOR RINGS AND DISCS Filed July 28, 1954 4 Sheets-Sheet 2 INVENTOR EDGAR HOMER KENDALL ATTORNEY arch 29, W60

E. H. KENDALL ROLLING MILL FOR RINGS AND DISCS Filed July 28, 1954 as El 4 Sheets-Sheet 3 n g 3 3558 w INVENTOR EDG AR HOMER KENDALL BY W M ATTORNEY March 29, 1960 E. H. KENDALL ROLLING MILL FOR RINGS AND DISCS 4 Sheets-Sheet 4 Filed July 28, 1954 U J Z4 I INVENTOR EDGAR HOMER KENDALL BY M w ATTORNEY United States Patent ROLLING MILL FOR RINGS AND DISCS Edgar Homer Kendall, Alliance, Ohio Application July 28, 1954, Serial No. 446,244

6 Claims. (Cl. 80-16) The present invention relates to metal forming apparatus, and more particularly to an improved mill apparatus for the rolling of circular shapes such as rings and discs, for example, from circular blanks of heated metal.

his the primary object of the present invention to provide a disc rolling mill of novel and improved design for rolling circular articles of large diameter to close final tolerances whereby such articles may be accurately finished with 'a minimum of further machine operations. The apparatus of my present invention is especially adapted for the rolling of rotor parts for high speed turbines, for example, which are of relatively large diameter and which are formed of high cost special alloys. Such materials are not only difiicult to machine, but machined scrap represents a substantial monetary waste. Thus, it

has been proposed to roll parts of this type to their approximate final dimensions whereby machining is required only for the purpose of bringing the parts to their final close tolerance dimensions.

One of the general objects of the invention is the pro vision of a ring or disc rolling apparatus operating upon a novel and improved principle whereby the circular shape of disc-like and ring-like parts may be accurately maintained throughout the rolling operation. It will of course be understood that in the rolling of large diameter circular parts if the final product is slightly out-ofround, even though the general dimensions such as rim thickness, diameter, and the like are accurately realized, substantial machining operations are required and substantial stock is wasted in finishing the article to its exact final form.

' Av more specific object of the invention resides in the provision of a ring or disc rolling mill of novel and improved design wherein a circular article is simultaneously worked and formed at a plurality of points about its periphery. In this respect my apparatus constitutes a substantial departure from the conventional, the prior practice generally providing for the working of the disc or ring at only one point or area about its periphery and guiding the article at other points for the purpose of maintaining the ring or disc in the proper relation to.

the working rolls and maintaining the roundness of the article as much as possible.

With further regard to the above object, the present invention seeks to provide a novel ring or disc rolling mill wherein a plurality of working rolls located at spaced points about the periphery of the article to be formed function to accurately guide the article and maintain its r'oundnessas well as to work and form the same in the desired manner.

7 Yet another object of the invention is the provision of a ring or disc rolling mill having a plurality of angularly related working rolls for simultaneously working and forming a single circular blank wherein is provided an improved arrangement for controlling the positioning of the plurality of working rolls during rolling operations so that accurate roundness ofthe finished article is assured.

A further object of the invention is the provision of a mill of the type above described having a plurality of working rolls acting at spaced points about the periphery of a circular =blank wherein is incorporated an improved arrangement for actuating the plurality of working rolls, the contemplated arrangement being of simplified nature while providing for accurate correlation of the speeds of the plurality of working rolls.

Other objects and advantages of the invention include variousspecific features of construction lending to simplicity and improvement in the construction and operation of the apparatus. Such and further objects and advantages of the invention will become apparent upon full consideration of the following detailed specification and accompanying drawing wherein is disclosed a certain preferred embodiment of the invention.

Figure 2 is an enlarged 'side elevation of one of a plurality of working stations incorporated in the apparatus of Figure 1; I

Figure 3 is a longitudinal section view of a working section of the type shownin Figure 2;

Figure 4 is a fragmentary section view taken substantially along line Iv -IV of Figure 3;

Figure 5 is an enlarged section view of a working rolland supporting and driving means therefor, all as incorporated into thev apparatus of Figure 1;

Figure 6 is a fragmentary section view taken substan-. tially along line VI-VI of Figure 5; and

Figure 7 is a fragmentary section view of the apparatus of Figure 5, showing certain detailed components thereof.

Referring now to the drawing, and initially to Figure 1 thereof, there is shown a disc rolling mill which, according to the teachings of my invention, is comprised of a plurality of angularly related working stations desig nated generally by numerals 10, 11 and 12 respectively. Many of the individual components of the stations 10-12 are identical or substantially identical in each, in which case identical numerals will be employed in making referenceto such components, without regard to the particular station in which such components may be iIlCOI'PO".

rated.

In the illustrated embodiment of the invention the working stations 10-12 are positioned upon axes which are related with respect to each other at angles of about 120 degrees. As shown in Figure 3, each working station comprises an upper working roll 13 and a lower working roll 14 which are adapted to act upon the upper and lower edges respectively of a circular blank 15. In addition, each working station includes a pair of pressure rolls 16 which are spaced on opposite sides of the principal axis of the working station and arranged to rods 18. Mounted on the rods 18, for longitudinal movement along the principal axis of the working station is a carriage 19, comprising a pair of spaced frame sections 20 which are secured together by means of a cross frame member 21 and tie rods 22 and 23.

Mounted on the carriage 19, 'in alignment with the Patented Mar-.29, 1960 principal axis of the working station, is a slide or carrier '24 which is guided for longitudinal movement by a guide member 25 forming a rigid part of the carriage 19. Preferably the carrier 24 and guide member 25 therefor are of rectangular or irregular cross section so that rotation of the carrier 24 is prevented. And mounted at the forward end of the carrier 24 is a yoke 26 which mounts the pressure rolls 16 for rotation about spaced vertical axes. The yoke 26 is vertically slidable with respect to the carrier 24, and an adjusting screw 27 is provided so that the yoke 26 may beset in any predetermined position.

Connecting the carrier 24 at the end thereof opposite the roll-carrying yoke 26 is the piston rod of a hydraulic cylinder 28 which is mounted on the cross frame member 21. Through suitable hydraulic control means, not shown, the cylinder 28 may be actuated toadjust the 1011- gitudinal position of the pressure rolls 16 with respect to the main carriage 19 and with respect to the working rolls 13 and 14.

Referring now to Figure of the drawing, the upper working roll 13 is shown to comprise a contoured outer end portion 13a, a frustro-conical neck portion 13b and a tapered shank portion 13c, the latter portion being snugly received in a correspondingly tapered opening or bore in the forward end of an elongated hollow driving member 29. The driving member is journaled by means of tapered antiriction bearings 30 and 31 in a bell-mouthed housing 32 in the manner shown. Preferably the end of the driving member 29 opposite the working roll 13 is exposed at the upper end of the housing 32. And received within the driving member 29, through the exposed end thereof, is a locking member 33, having a threaded lower end 34 and a fiangedupper end 35 which is provided with suitable wrench flats, not specifically shown. The arrangement is such that the tapered shank portion 130 of the working roll 13 may be engaged and drawn tightly into the tapered socket therefor provided in the driving member so that while the working roll 13 is readily removable power may be etfectively applied thereto through the driving member 29.

Secured to the upper end of the driving member 29 and housed within the enlarged upper end portion of the housing 29 is a driving gear 36 having internal gear teeth thereon which mesh with a driving pinion 37 carried on the power shaft of a hydraulic drive motor 38. The motor 33 may be conveniently mounted upon an apertured cover plate 39 which serves to enclose the enlarged open end of the housing 32, except for a central opening through which the driving member 29 lies exposed.

In the illustrated apparatus the drive housing 32 .is provided intermediate its ends with outwardly extending trunnions 40 (see Figure 6) which are engaged by journals 41 of an upper roll-supporting frame, designated generally by the numeral 42. The roll-supporting frame 42 may be of welded or cast construction, having an opening 43 in its lower forward end for the reception of the forward end portion of the drive member 29, and having a cylindrical journal portion 44 at its opposite end, below the housing 32, for the reception of a supporting shaft 45. In the preferred embodiment of the invention the supporting shaft is journaled at 46 in the main frame sections 20 of the carriage 19, and supports the roll-supporting frame 42 in eccentric relation to the journals 46. Thus, the position of the frame 42, housing 32 and working roll 13, as a unit, may be varied slightly with respect to the carriage 19.

For the purpose of rotating the eccentric supporting shaft 45 there is provided at one side of the carriage (see Figure 2) a hand wheel 46' operating through suitable worm gearing 47 or other mechanism.

Generally the eccentric shaft 45 will be fixed in its adjusted position. Thus, toefiect normal movements of the working roll 13 with respect to the carriage 19 there is mounted at the upper end of the carriage a hydraulic cylinder 48, the operating rod of which connects the rollsupporting frame 42 at the upper forward portion of the latter, as indicated at 49. Preferably the cylinder 48 is of the type having a rod 50 extending from its upper end and adjustable abutment or stop means 51 carried by the rod 50 whereby the downward or extending movement of the main operatingrod of the cylinder may be positively and accurately limited.

During loading of circular blanks into the rolling mill the cylinder 48 is retracted so that the frame 42 is pivoted upwardly about the eccentric supporting shaft 45, moving the upper working roll 13 to an out-of-the-way position so that a blank 15 may be moved horizontally into rolling position. The cylinder may then be extended, and full operating pressure applied thereto, so that the upper roll 13 is moved downwardly until the adjustable limit stop 51 is engaged.

An important object of the invention is the provision of a rolling mill having a plurality of working stations 1012, each with upper and lower working rolls 13 and 14, wherein the working rolls may be closely converged at the beginning of a rolling operation. To this end the rolls themselves, and the immediate supporting structure therefor must be of minimum cross section so as not to interfere with other structural parts of the apparatus as the rolls are caused to converge. Accordingly, immediately above the upper working roll 13 I have mounted a pair of spaced back-up rolls 52 having tapered back-up surfaces thereon which engage the frustro-conical neck portion 13b of the roll 13. The back-up rolls 52 are journaled rigidly in the frame 42, as shown in Figure 7, and constitute substantially the sole supporting means for the roll 13 so far as actual working loads and pressures are concerned. This arrangement is advantageous in that the forward neck portion of the drive member 29 may be of small diameter and cross section, as may the roll 13 itself. The back-up forces are applied to the roll 13 immediately adjacent the working head 13a thereof so that advantageous leverages are afforded. Moreover, it will be noted that in positioning a pair of back-up rolls 52 one on each upper side of the working roll 13 the latter is fully stabilized against lateral as well as vertical deilections.

A simplified arrangement for mounting the back-up rolls 53 is shown in Figure 7. The body or section of the frame 42 is of course rather heavy adjacent the working roll 13, and received and secured within spaced bores in the frame 42 are stout journal shafts 53. A portion of each shaft 53 extends forwardly of the front face of the frame 43 for the reception of a suitable anti-friction bearing 54 which in turn supports the back-up roll 52.

And to secure the bearing 54 and roll 52 in position there is provided a flanged member 55 which engages the roll 52 adjacent its front face and extends through the center of the. journal shaft 53, being secured at the inner end thereof.

Referring again to Figure 3, it will be observed that the supporting and driving assembly for the lower working roll 14 is substantially identical to that for the upper working roll 13, as described therein. Separate and further description of such assembly will therefore be omitted. However, it should be noted that the supporting frame 42' for the lower working roll assembly is generally fixed in position, whereas the upper frame 42 may be pivoted about its supporting shaft upon actuation of the cylinder 48. Thus, journaled on the lower tie rod 23 is a connecting member 56 having a cylindrical recess in its upper side for the reception of a threaded adjusting rod 57. The rod 57 is threaded at its upper end for adjustable engagement with a yoke 58 which is pivotally attached at 59 to the lower roll-supporting frame 42'. Upon rotation of the rod 57 in a desired direction the frame 42 may be raised or lowered slightly relative to the carriage 19. Generally the rod 57 will be adjusted to. suit the type of roll 14 employed and the work to be accommodated, after which there will be no further adjustrnents, except perhaps certain correcting adjustments which may be necessary from time to time. I

. During the rolling of a circular blank 15 the same will progressively increase in diameter, in which case it is necessary to progressively back ofl? the plurality of carriages 19 along their respective working axes. For this purpose I provide a threaded sleeve 60in the rear cross frame member 21 of each carriage (see Figure 3) which is engaged by a longitudinally extending threaded shaft 61. The shaft 61 extends to and is suitably journaled in a gear box 62 positioned at the end of the frame 17.

Within the gear box 62 the shaft 61 mounts a bevel gear 63 and an overrunning clutch 64. And the extreme outer end of the shaft 61 is engaged with a hydraulic motor 65 mounted at the side of the gear box 62. On the outer and normally the driving member of the overrunning clutch 64 there is" mounted a large diameter gear 65 which meshes with a small pinion 66 driven by a second hydraulic motor 67. The clutch 64 is so arranged that upon proper rotation of the second motor 67 the shaft 61 is driven through the clutch in a proper direction to cause retraction of the carriage '19 along its supporting rods 18.

For rapid traverse movements of the carriage 19 the larger hydraulic motor 65 is energized, providing a direct full speed drive for the shaft 61. During rapid retracting movements of'the carriage 19 the clutch 64 merely overruns, as will be understood.

In accordance with the teachings of the invention the several carriages 19 are retracted in exact synchronism during a rolling operation so that as the circular blank expands its circular configuration is accurately maintained'.,1To this end I have provided a pairof drive shafts 68 which extend from the gear box 62 to similar gear boxes 69 of working stations 11 and 12. As shown Figure 4 the drive shafts "68 mount 'bevel gears 68 at their inner ends which mesh with the bevel gear 63 carried-upon the threaded shaft 61. At the outer ends of thedrive shafts 68similar bevel gears, not specifically shown, are provided within gear boxes 69 which mesh with other gears; also not specifically shown, to drive threaded shafts 70 and 71, causing the carriages 19 of work stations 11 and 12 to advance or retract as the case maybe.

Thus, at the start of a disc or ringrollingoperation the carriages 19 are caused to converge, and the working rolls are lowered onto the circular blank by suitable actuation of cylinders 48. All the pairs of working rolls are then rotated by the plurality of hydraulic drive motors 38, and the carriages 19 are caused to retract in exact synchronism, by the hydraulic motor 67, as the blank expands. The pressure rolls 16 of each working station act in conjunction with the working rolls 13 and 14 of the same station to accurately confine and properly work and shape the edges of the blank 15. The several cooperating sets of rolls are maintained in accurate relation to a predetermined center axis so that at all times the blank 15 is rotated about such center point or axis, without the aid of further guiding and confining rolls, as such. The result is that substantially more accurate control is had over the dimensions and shape of the blank 15 so that a practical minimum of excess stock need be provided for finish machining operations.

In order to correlate the speeds of the several sets of working rolls I have provided a novel driving arrangement, shown schematically in Figure l, which comprises the hydraulic driving motors 38 and a hydraulic operating circuit therefor in which all of the drive motors for the upper working rolls 14, for example, are connected in series with a single pump and control valve. The drive motors 38 are of course of the positive displacement type so that for a given flow of fluid therethrough there is necessarily resulting a predetermined motor movement. Thus, a suitable hydraulic pump 72 is connected through. a flow control valve 73 to conduits 74-77 respectively which are connected in series with each of the drive motors for the upper working rolls 13. As will be readily understood, manipulation of the valve 73 will effect simultaneous and equal speed regulation of the several drive motors so that roll slippage and distortion of the circular blank will be eliminated, insofar as possible. 7

Of course, a similar actuating and control system, not specifically shown, is provided for the lower working roll drive motors. Generally the upper and lower working rolls will be of different sizes, and will therefore be driven at different speeds. However, in each instance, all the drive motors of each set will be simultaneously and identically controlledthrough single control valves;

It should thus be apparent that I have accomplished the various objects initially set forth. My novel disc or ring rolling mill departs substantially from conventional designs in providing a plurality of angularly related simultaneously controlled working stations, each having a complete set of working and pressure rolls, so that a disc or ring'blank is subjected to simultaneous and continuous working at several points about its periphery whereby accurate control and guidance of the blank is obtained and working tolerances may be substantially reduced; During a rolling operation, as the circular blank expands, all of the several working stations are retracted in exact synchronism through mechanically insets of rolls so that undesirable distortion of the blank is eliminated or materially reduced. And tothis same end, there is provided a novel driving system for the various working rolls whereby the same are maintained at synchronous speeds and whereby equal and simultaneous speed adjustments may be effected when necessary or desirable.

e Other novel features of the invention include specific features of construction of the working stations themselves, including the roll housing and supporting arrange ment which permits the rolls to be'converged as far as possible toward the axis of rotation of the blank, to ac commodate blanks of small diameter. Y It should be understood, however, that the embodiment herein specifically described and illustrated is intended to be illustrative only of the invention, as many changes may be made therein within the clear teachings of the disclosure. Reference should therefore be had to the following appended claims in determining the full scope of the invention.

I claim:

1. In a rolling mill for metal discs and the like of the type having a plurality of angularly related working stations, the combination of a plurality of at least three angularly related working roll supporting carriages, a

working roll supporting housing for each carriage, means to pivotally mount said housings on said carriages, power means to pivot said housings through a substantial arc toward and away from working positions, a positive displacement hydraulic drive motor mounted on each housing and connected in driving relation with the working rolls thereof, means to move said carriages in unison toward and away from each other, and power means for said drive motors comprising a hydraulic system connecting said motors in series relation whereby upon the flow of fluid through said system said motors are driven at identical speeds.

2. In a rolling mill for metal discs and the like of the type having a plurality of angularly related working stations the combination of a plurality of at least three angularly related working roll supporting carriages adapted for movement toward and away from each other, a working roll supporting frame mounted for pivoting movement on each of said carriages", a hydraulic actuator connecting each carriage with the frame supportedthe'reon for forcibly moving said frames toward'a working plane, a working roll housing for each fram'e', each such roll housing rotatably mounting a forwardly projecting small diameter workingroll, said working rolls having inwardly tapering frusto-conical neck portions adjacent their outer end portions, pairs of frusto-conical back-up rolls journaled on said roll mounting frames along axes intersecting with the axes of said working rolls, and cantilever spindlescarried by said frames and journaling said back-up rolls at their free outer ends.

3. In a rolling mill for metal discs and'the like of the type having a plurality of angularly related working stations the combination of a plurality of at least three angularly 'related working roll supporting carriages adapted for movement toward and away from each other, a working roll supporting frame mounted for pivoting movement on each of said carriages, driving :means "connecting each carriage with the frame supported thereon for forcibly moving said frames toward a working plane, a working roll housing for each frame, each such roll housing rotatably mounting a forwardly projectingsmall diameter working roll, said working roll "having inwardly tapering frusto-conical neck portions adjacent their outer end portions, frusto-conical back-up rolls journaled on said roll supporting frames along'axes intersecting with the axes of said working rolls, and cantilever spindles carried by said frames and journaling said back-up rolls at their outer free ends.

4. In a rolling mill for metal discs and the like of the type having a plurality of angularly related working stations, each of said working stations comprising a base portion and a carriage movable on said base portion toward and away from a fixed point, means for synchronizing the movement of said carriages whereby said carriages move toward and away from said fixed point in exact synchronism, each of said carriages having a working roll supporting housings, means to pivotally mount said housing on said carriages, power means to pivot said housings toward and away from working positions, means at each of said working stations for mov ing said carriage on said base portion, said last mentioned means comprising a shaft for each of said working stations journaled in said base portion and having a driving threaded connection with said carriage, means for powering said shafts including a first high speed motor coupled directly with one of said shafts, a second that said means-for synchronizing the movement' of said carriages comprises mechanical drive shafts each interconnected with said one of said shafts and ano'thcrof said shafts for driving the same.

'6. In a rolling mill for metal discs and the like the combination of a plurality of at least three angularly related working stations, each of said working station's comprising a base portion and a carriage movable on said base portion toward and -away from a fixed point, means at each of said working stations for moving said carriages on said base portion, means for synchronizing the movement of said carriages whereby said "carriages move toward and away from said fixed point in exact s'ynchronism, each of said carriages pivotally mounting a pair of opposed working rolls for acting on the upper and lower edges of a circular blank, pivoting mean's mounted on each of said carriages for pivoting said'opposed working rolls toward and 'away' from working positions, means to drive all of said working rolls in exact synchronism, a pressure roll carried by each of said carriages in movable relation thereto and adapted to act in opposition to said working rolls upon the outer peripheral surface of said blank, and said blank being supported and guided solely by said working rolls and said pressure rolls.

References Cited in the file of this patent UNITED STATES PATENTS 1,327,635 Slick Jan. 13, 1,350,057 Bell Aug. 17, 1920 2,109,392 Le Bleu Feb. 22, 1933 2,112,466 Maloon Mar. 29, 1 9315 2,144,735 Granberg Jan. 24, 1939 2,307,191 Bell Jan. 5, 194; 2,520,014 Rehuberg Aug. 22, 1950 2,651,239 Schlagel 5. Sept. 8,195; 2,728,974 Miller Jan. 3, 1956 FOREIGN PATENTS 1,029 Great Britain Mar. 9, 1880 895,596 France Apr. 3, 1944 

